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- /*******************************************************************************
- * CTS_HAL.c - defines functions called by application as well as
- * functions for information processing
- *
- * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the
- * distribution.
- *
- * Neither the name of Texas Instruments Incorporated nor the names of
- * its contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- ******************************************************************************/
-
- /***************************************************************************//**
- * @file CTS_HAL.c
- *
- * @brief
- *
- * @par Project:
- * MSP430 Capacitive Touch Library
- *
- * @par Developed using:
- * IAR Version : 5.10.6 [Kickstart] (5.10.6.30180)
- * CCS Version : 4.2.1.00004, w/support for GCC extensions (--gcc)
- *
- * @version 1.0.0 Initial Release
- *
- * @par Supported API Calls:
- * - TI_CAPT_Init_Baseline()
- * - TI_CAPT_Update_Baseline()
- * - TI_CAPT_Reset_Tracking()
- * - TI_CAPT_Update_Tracking_DOI()
- * - TI_CAPT_Update_Tracking_Rate()
- * - TI_CAPT_Update_Baseline()
- * - TI_CAPT_Raw()
- * - TI_CAPT_Custom()
- * - TI_CAPT_Button()
- * - TI_CAPT_Buttons()
- * - TI_CAPT_Slider()
- * - TI_CAPT_Wheel()
- ******************************************************************************/
-
- #include "CTS_Layer.h"
- #include <stdlib.h>
-
- // Global variables for sensing
- #ifdef TOTAL_NUMBER_OF_ELEMENTS
- uint16_t baseCnt[TOTAL_NUMBER_OF_ELEMENTS];
- #ifdef RAM_FOR_FLASH
- uint16_t measCnt[MAXIMUM_NUMBER_OF_ELEMENTS_PER_SENSOR];
- #endif
- uint16_t ctsStatusReg = (DOI_INC+TRADOI_FAST+TRIDOI_SLOW);
- #endif
-
- /***************************************************************************//**
- * @addtogroup CTS_API
- * @{
- ******************************************************************************/
-
-
- /***************************************************************************//**
- * @brief Measure the capacitance of each element within the Sensor
- *
- * This function selects the appropriate HAL to perform the capacitance
- * measurement based upon the halDefinition found in the sensor
- * structure.
- * The order of the elements within the Sensor structure is arbitrary
- * but must be consistent between the application and configuration.
- * The first element in the array (counts) corresponds to the first
- * element within the Sensor structure.
- * @param groupOfElements Pointer to Sensor structure to be measured
- * @param counts Address to where the measurements are to be written
- * @return none
- ******************************************************************************/
- void TI_CAPT_Raw(const struct Sensor* groupOfElements, uint16_t * counts)
- {
- #ifdef RO_COMPAp_TA0_WDTp
- if(groupOfElements->halDefinition == RO_COMPAp_TA0_WDTp)
- {
- TI_CTS_RO_COMPAp_TA0_WDTp_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef fRO_COMPAp_TA0_SW
- if(groupOfElements->halDefinition == fRO_COMPAp_TA0_SW)
- {
- TI_CTS_fRO_COMPAp_TA0_SW_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef fRO_COMPAp_SW_TA0
- if(groupOfElements->halDefinition == fRO_COMPAp_SW_TA0)
- {
- TI_CTS_fRO_COMPAp_SW_TA0_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef RO_COMPAp_TA1_WDTp
- if(groupOfElements->halDefinition == RO_COMPAp_TA1_WDTp)
- {
- TI_CTS_RO_COMPAp_TA1_WDTp_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef fRO_COMPAp_TA1_SW
- if(groupOfElements->halDefinition == fRO_COMPAp_TA1_SW)
- {
- TI_CTS_fRO_COMPAp_TA1_SW_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef RC_PAIR_TA0
- if(groupOfElements->halDefinition == RC_PAIR_TA0)
- {
- TI_CTS_RC_PAIR_TA0_HAL(groupOfElements, counts); // Measure all sensors
- }
- #endif
-
- #ifdef RO_PINOSC_TA0_WDTp
- if(groupOfElements->halDefinition == RO_PINOSC_TA0_WDTp)
- {
- TI_CTS_RO_PINOSC_TA0_WDTp_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef RO_PINOSC_TA0
- if(groupOfElements->halDefinition == RO_PINOSC_TA0)
- {
- TI_CTS_RO_PINOSC_TA0_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef fRO_PINOSC_TA0_SW
- if(groupOfElements->halDefinition == fRO_PINOSC_TA0_SW)
- {
- TI_CTS_fRO_PINOSC_TA0_SW_HAL(groupOfElements, counts); // Measure all sensors
- }
- #endif
-
- #ifdef RO_COMPB_TA0_WDTA
- if(groupOfElements->halDefinition == RO_COMPB_TA0_WDTA)
- {
- TI_CTS_RO_COMPB_TA0_WDTA_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef fRO_COMPB_TA0_SW
- if(groupOfElements->halDefinition == fRO_COMPB_TA0_SW)
- {
- TI_CTS_fRO_COMPB_TA0_SW_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef RO_COMPB_TA1_WDTA
- if(groupOfElements->halDefinition == RO_COMPB_TA1_WDTA)
- {
- TI_CTS_RO_COMPB_TA1_WDTA_HAL(groupOfElements, counts);
- }
- #endif
-
- #ifdef fRO_COMPB_TA1_SW
- if(groupOfElements->halDefinition == fRO_COMPB_TA1_SW)
- {
- TI_CTS_fRO_COMPB_TA1_SW_HAL(groupOfElements, counts);
- }
- #endif
- }
-
- #ifdef TOTAL_NUMBER_OF_ELEMENTS
- /***************************************************************************//**
- * @brief Make a single capacitance meausrment to initialize baseline tracking
- * @param groupOfElements Pointer to Sensor structure to be measured
- * @return none
- ******************************************************************************/
- void TI_CAPT_Init_Baseline(const struct Sensor* groupOfElements)
- {
- TI_CAPT_Raw(groupOfElements, &baseCnt[groupOfElements->baseOffset]);
- }
-
- /***************************************************************************//**
- * @brief Update baseline tracking by averaging several measurements
- * @param groupOfElements Pointer to Sensor structure to be measured
- * @param numberofAverages Number of measurements to be averaged
- * @return none
- ******************************************************************************/
- void TI_CAPT_Update_Baseline(const struct Sensor* groupOfElements, uint8_t numberOfAverages)
- {
- uint8_t i,j;
- #ifndef RAM_FOR_FLASH
- uint16_t *measCnt;
- measCnt = (uint16_t *)malloc(groupOfElements->numElements * sizeof(uint16_t));
- if(measCnt ==0)
- {
- while(1);
- }
- #endif
- for(j=0; j < numberOfAverages; j++)
- {
- for(i=0; i < groupOfElements->numElements; i++)
- {
- TI_CAPT_Raw(groupOfElements, measCnt);
- baseCnt[i+groupOfElements->baseOffset] = measCnt[i]/2 + baseCnt[i+groupOfElements->baseOffset]/2;
- }
- }
- #ifndef RAM_FOR_FLASH
- free(measCnt);
- #endif
- }
-
- /***************************************************************************//**
- * @brief Reset the Baseline Tracking algorithm to the default state
- * @param none
- * @return none
- ******************************************************************************/
- void TI_CAPT_Reset_Tracking(void)
- {
- ctsStatusReg = (DOI_INC+TRADOI_FAST+TRIDOI_SLOW);
- }
-
- /***************************************************************************//**
- * @brief Update the Baseline Tracking algorithm Direction of Interest
- * @param direction Direction of increasing or decreasing capacitance
- * @return none
- ******************************************************************************/
- void TI_CAPT_Update_Tracking_DOI(uint8_t direction)
- {
- if(direction)
- {
- ctsStatusReg |= DOI_INC;
- }
- else
- {
- ctsStatusReg &= ~DOI_INC;
- }
- }
-
- /***************************************************************************//**
- * @brief Update the baseling tracking algorithm tracking rates
- * @param rate Rate of tracking changes in and against direction of intrest
- * @return none
- ******************************************************************************/
- void TI_CAPT_Update_Tracking_Rate(uint8_t rate)
- {
- ctsStatusReg &= ~(TRIDOI_FAST+TRADOI_VSLOW); // clear fields
- ctsStatusReg |= (rate & 0xF0); // update fields
- }
-
- /***************************************************************************//**
- * @brief Measure the change in capacitance of the Sensor
- *
- * This function measures the change in capacitance of each element
- * within a sensor and updates the baseline tracking in the event that
- * no change exceeds the detection threshold.
- * The order of the elements within the Sensor structure is arbitrary
- * but must be consistent between the application and configuration.
- * The first element in the array (deltaCnt) corresponds to the first
- * element within the Sensor structure.
- * @param groupOfElements Pointer to Sensor structure to be measured
- * @param deltaCnt Address to where the measurements are to be written
- * @return none
- ******************************************************************************/
- void TI_CAPT_Custom(const struct Sensor* groupOfElements, uint16_t * deltaCnt)
- {
- uint8_t j;
- uint16_t tempCnt;
- ctsStatusReg &= ~ EVNT;
-
- // This section calculates the delta counts*************************************
- //******************************************************************************
- TI_CAPT_Raw(groupOfElements, &deltaCnt[0]); // measure group of sensors
-
- for (j = 0; j < (groupOfElements->numElements); j++)
- {
- tempCnt = deltaCnt[j];
- if(((ctsStatusReg & DOI_MASK) && (groupOfElements->halDefinition & RO_MASK))
- ||
- ((!(ctsStatusReg & DOI_MASK)) && (!(groupOfElements->halDefinition & RO_MASK))))
- {
- // RO method, interested in an increase in capacitance
- if(baseCnt[j+groupOfElements->baseOffset] < deltaCnt[j])
- {
- // If capacitance decreases, then measCnt is greater than base
- // , set delta to zero
- deltaCnt[j] = 0;
- // Limit the change in the opposite direction to the threshold
- if(((groupOfElements->arrayPtr[j])->threshold)
- &&
- (baseCnt[j+groupOfElements->baseOffset]+(groupOfElements->arrayPtr[j])->threshold < tempCnt))
- {
- tempCnt = baseCnt[j+groupOfElements->baseOffset]+(groupOfElements->arrayPtr[j])->threshold;
- }
- }
- else
- {
- // change occuring in our DOI, save result
- deltaCnt[j] = baseCnt[j+groupOfElements->baseOffset]-deltaCnt[j];
- }
- }
- if(((!(ctsStatusReg & DOI_MASK)) && (groupOfElements->halDefinition & RO_MASK))
- ||
- ((ctsStatusReg & DOI_MASK) && (!(groupOfElements->halDefinition & RO_MASK))))
- {
- // RO method: interested in a decrease in capactiance
- // measCnt is greater than baseCnt
- if(baseCnt[j+groupOfElements->baseOffset] > deltaCnt[j])
- {
- // If capacitance increases, set delta to zero
- deltaCnt[j] = 0;
- // Limit the change in the opposite direction to the threshold
- if(((groupOfElements->arrayPtr[j])->threshold)
- &&
- (baseCnt[j+groupOfElements->baseOffset] > tempCnt+(groupOfElements->arrayPtr[j])->threshold))
- {
- tempCnt = baseCnt[j+groupOfElements->baseOffset]-(groupOfElements->arrayPtr[j])->threshold;
- }
- }
- else
- {
- // change occuring in our DOI
- deltaCnt[j] = deltaCnt[j] - baseCnt[j+groupOfElements->baseOffset];
- }
- }
-
- // This section updates the baseline capacitance****************************
- //**************************************************************************
- if (deltaCnt[j]==0)
- { // if delta counts is 0, then the change in capacitance was opposite the
- // direction of interest. The baseCnt[i] is updated with the saved
- // measCnt value for the current index value 'i'.
- switch ((ctsStatusReg & TRADOI_VSLOW))
- {
- case TRADOI_FAST://Fast
- tempCnt = tempCnt/2;
- baseCnt[j+groupOfElements->baseOffset] = (baseCnt[j+groupOfElements->baseOffset]/2);
- break;
- case TRADOI_MED://Medium
- tempCnt = tempCnt/4;
- baseCnt[j+groupOfElements->baseOffset] = 3*(baseCnt[j+groupOfElements->baseOffset]/4);
- break;
- case TRADOI_SLOW://slow
- tempCnt = tempCnt/64;
- baseCnt[j+groupOfElements->baseOffset] = 63*(baseCnt[j+groupOfElements->baseOffset]/64);
- break;
- case TRADOI_VSLOW://very slow
- tempCnt = tempCnt/128;
- baseCnt[j+groupOfElements->baseOffset] = 127*(baseCnt[j+groupOfElements->baseOffset]/128);
- break;
- }
- // set X, Y & Z, then perform calculation for baseline tracking:
- // Base_Capacitance = X*(Measured_Capacitance/Z) + Y*(Base_Capacitance/Z)
- baseCnt[j+groupOfElements->baseOffset] = (tempCnt)+(baseCnt[j+groupOfElements->baseOffset]);
- }
- // delta counts are either 0, less than threshold, or greater than threshold
- // never negative
- else if(deltaCnt[j]<(groupOfElements->arrayPtr[j])->threshold && !(ctsStatusReg & PAST_EVNT))
- { //if delta counts is positive but less than threshold,
- switch ((ctsStatusReg & TRIDOI_FAST))
- {
- case TRIDOI_VSLOW://very slow
- if(deltaCnt[j] > 15)
- {
- if(tempCnt < baseCnt[j+groupOfElements->baseOffset])
- {
- baseCnt[j+groupOfElements->baseOffset] = baseCnt[j+groupOfElements->baseOffset] - 1;
- }
- else
- {
- baseCnt[j+groupOfElements->baseOffset] = baseCnt[j+groupOfElements->baseOffset] + 1;
- }
- }
- tempCnt = 0;
- break;
- case TRIDOI_SLOW://slow
- if(tempCnt < baseCnt[j+groupOfElements->baseOffset])
- {
- baseCnt[j+groupOfElements->baseOffset] = baseCnt[j+groupOfElements->baseOffset] - 1;
- }
- else
- {
- baseCnt[j+groupOfElements->baseOffset] = baseCnt[j+groupOfElements->baseOffset] + 1;
- }
- tempCnt = 0;
- break;
- case TRIDOI_MED://medium
- tempCnt = tempCnt/4;
- baseCnt[j+groupOfElements->baseOffset] = 3*(baseCnt[j+groupOfElements->baseOffset]/4);
- break;
- case TRIDOI_FAST://fast
- tempCnt = tempCnt/2;
- baseCnt[j+groupOfElements->baseOffset] = (baseCnt[j+groupOfElements->baseOffset]/2);
- break;
- }
- // set X, Y & Z, then perform calculation for baseline tracking:
- // Base_Capacitance = X*(Measured_Capacitance/Z) + Y*(Base_Capacitance/Z)
- baseCnt[j+groupOfElements->baseOffset] = (tempCnt)+(baseCnt[j+groupOfElements->baseOffset]);
- }
- //if delta counts above the threshold, event has occurred
- else if(deltaCnt[j]>=(groupOfElements->arrayPtr[j])->threshold)
- {
- ctsStatusReg |= EVNT;
- ctsStatusReg |= PAST_EVNT;
- }
- }// end of for-loop
- if(!(ctsStatusReg & EVNT))
- {
- ctsStatusReg &= ~PAST_EVNT;
- }
- }
-
- /***************************************************************************//**
- * @brief Determine if a button is being pressed
- * @param groupOfElements Pointer to button to be scanned
- * @return result Indication if button is (1) or is not (0) being pressed
- ******************************************************************************/
- uint8_t TI_CAPT_Button(const struct Sensor * groupOfElements)
- {
- uint8_t result = 0;
-
- #ifndef RAM_FOR_FLASH
- uint16_t *measCnt;
- measCnt = (uint16_t *)malloc(groupOfElements->numElements * sizeof(uint16_t));
- if(measCnt ==0)
- {
- while(1);
- }
- #endif
-
- TI_CAPT_Custom(groupOfElements, measCnt);
- #ifndef RAM_FOR_FLASH
- free(measCnt);
- #endif
- if(ctsStatusReg & EVNT)
- {
- result = 1;
- }
- return result;
- }
-
- /***************************************************************************//**
- * @brief Determine which button if any is being pressed
- * @param groupOfElements Pointer to buttons to be scanned
- * @return result pointer to element (button) being pressed or 0 none
- ******************************************************************************/
- const struct Element *TI_CAPT_Buttons(const struct Sensor *groupOfElements)
- {
- uint8_t index;
- #ifndef RAM_FOR_FLASH
- uint16_t *measCnt;
- measCnt = (uint16_t *)malloc(groupOfElements->numElements * sizeof(uint16_t));
- if(measCnt ==0)
- {
- while(1);
- }
- #endif
- TI_CAPT_Custom(groupOfElements, measCnt);
-
- if(ctsStatusReg & EVNT)
- {
- index = Dominant_Element(groupOfElements, measCnt);
- //ctsStatusReg &= ~EVNT;
- index++;
- }
- else
- {
- index = 0;
- }
- #ifndef RAM_FOR_FLASH
- free(measCnt);
- #endif
- if(index)
- {
- return groupOfElements->arrayPtr[index-1];
- }
- return 0;
- }
-
- #ifdef SLIDER
- /***************************************************************************//**
- * @brief Determine the position on a slider
- * @param groupOfElements Pointer to slider
- * @return result position on slider or illegal value if no touch
- ******************************************************************************/
- uint16_t TI_CAPT_Slider(const struct Sensor* groupOfElements)
- {
- uint8_t index;
- int16_t position;
- // allocate memory for measurement
- #ifndef RAM_FOR_FLASH
- uint16_t *measCnt;
- measCnt = (uint16_t *)malloc(groupOfElements->numElements * sizeof(uint16_t));
- if(measCnt ==0)
- {
- while(1);
- }
- #endif
- position = ILLEGAL_SLIDER_WHEEL_POSITION;
- //make measurement
- TI_CAPT_Custom(groupOfElements, measCnt);
-
- // Use EVNT flag to determine if slider was touched.
- // The EVNT flag is a global variable and managed within the TI_CAPT_Custom function.
- if(ctsStatusReg & EVNT)
- {
- index = Dominant_Element(groupOfElements, &measCnt[0]);
- // The index represents the element within the array with the highest return.
- if(index == 0)
- {
- // Special case of 1st element in slider, add 1st, last, and 2nd
- position = measCnt[0] + measCnt[1];
- }
- else if(index == (groupOfElements->numElements -1))
- {
- // Special case of Last element in slider, add last, 1st, and 2nd to last
- position = measCnt[groupOfElements->numElements -1] + measCnt[groupOfElements->numElements -2];
- }
- else
- {
- position = measCnt[index] + measCnt[index+1] + measCnt[index-1];
- }
- // Determine if sensor threshold criteria is met
- if(position > groupOfElements->sensorThreshold)
- {
- // calculate position
- position = index*(groupOfElements->points/groupOfElements->numElements);
- position += (groupOfElements->points/groupOfElements->numElements)/2;
- if(index == 0)
- {
- // Special case of 1st element in slider, which only has one
- // neighbor, measCnt[1]. measCnt is limited to maxResponse
- // within dominantElement function
- if(measCnt[1])
- {
- position += (measCnt[1]*(groupOfElements->points/groupOfElements->numElements))/100;
- }
- else
- {
- position = (measCnt[0]*(groupOfElements->points/groupOfElements->numElements)/2)/100;
- }
- }
- else if(index == (groupOfElements->numElements -1))
- {
- // Special case of Last element in slider, which only has one
- // neighbor, measCnt[x-1] or measCnt[numElements-1]
- if(measCnt[index-1])
- {
- position -= (measCnt[index-1]*(groupOfElements->points/groupOfElements->numElements))/100;
- }
- else
- {
- position = groupOfElements->points;
- position -= (measCnt[index]*(groupOfElements->points/groupOfElements->numElements)/2)/100;
- }
- }
- else
- {
- position += (measCnt[index+1]*(groupOfElements->points/groupOfElements->numElements))/100;
- position -= (measCnt[index-1]*(groupOfElements->points/groupOfElements->numElements))/100;
- }
- if((position > groupOfElements->points) || (position < 0))
- {
- position = ILLEGAL_SLIDER_WHEEL_POSITION;
- }
- }
- else
- {
- position = ILLEGAL_SLIDER_WHEEL_POSITION;
- }
- }
- #ifndef RAM_FOR_FLASH
- free(measCnt);
- #endif
- return position;
- }
- #endif
-
- #ifdef WHEEL
- /***************************************************************************//**
- * @brief Determine the position on a wheel
- * @param groupOfElements Pointer to wheel
- * @return result position on wheel or illegal value if no touch
- ******************************************************************************/
- uint16_t TI_CAPT_Wheel(const struct Sensor* groupOfElements)
- {
- uint8_t index;
- int16_t position;
- // allocate memory for measurement
- #ifndef RAM_FOR_FLASH
- uint16_t *measCnt;
- measCnt = (uint16_t *)malloc(groupOfElements->numElements * sizeof(uint16_t));
- if(measCnt ==0)
- {
- while(1);
- }
- #endif
- position = ILLEGAL_SLIDER_WHEEL_POSITION;
- //make measurement
- TI_CAPT_Custom(groupOfElements, measCnt);
- // Translate the EVNT flag from an element level EVNT to a sensor level EVNT.
- // The sensor must read at least 75% cumulative response before indicating a
- // touch.
- if(ctsStatusReg & EVNT)
- {
- index = Dominant_Element(groupOfElements, &measCnt[0]);
- // The index represents the element within the array with the highest return.
- //
- if(index == 0)
- {
- // Special case of 1st element in slider, add 1st, last, and 2nd
- position = measCnt[0] + measCnt[groupOfElements->numElements -1] + measCnt[1];
- }
- else if(index == (groupOfElements->numElements -1))
- {
- // Special case of Last element in slider, add last, 1st, and 2nd to last
- position = measCnt[index] + measCnt[0] + measCnt[index-1];
- }
- else
- {
- position = measCnt[index] + measCnt[index+1] + measCnt[index-1];
- }
- if(position > groupOfElements->sensorThreshold)
- {
- //index = Dominant_Element(groupOfElements, &measCnt[0]);
- // The index represents the element within the array with the highest return.
- //
- position = index*(groupOfElements->points/groupOfElements->numElements);
- position += (groupOfElements->points/groupOfElements->numElements)/2;
- if(index == 0)
- {
- // Special case of 1st element in slider, which only has one neighbor, measCnt[1]
- // measCnt is limited to maxResponse within dominantElement function
- position += (measCnt[1]*(groupOfElements->points/groupOfElements->numElements))/100;
- position -= (measCnt[groupOfElements->numElements -1]*(groupOfElements->points/groupOfElements->numElements))/100;
- if(position < 0)
- {
- position = position + (int16_t)groupOfElements->points;
- }
- }
- else if(index == (groupOfElements->numElements -1))
- {
- // Special case of Last element in slider, which only has one neighbor, measCnt[x-1] or measCnt[numElements-1]
- // measCnt is limited to maxResponse within dominantElement function
- position += (measCnt[0]*(groupOfElements->points/groupOfElements->numElements))/100;
- position -= (measCnt[index-1]*(groupOfElements->points/groupOfElements->numElements))/100;
- if(position > (groupOfElements->points -1))
- {
- position = position - (int16_t)groupOfElements->points;
- }
- }
- else
- {
- position += (measCnt[index+1]*(groupOfElements->points/groupOfElements->numElements))/100;
- position -= (measCnt[index-1]*(groupOfElements->points/groupOfElements->numElements))/100;
- }
- if((position > groupOfElements->points) || position < 0)
- {
- position = ILLEGAL_SLIDER_WHEEL_POSITION;
- }
- }
- else
- {
- position = ILLEGAL_SLIDER_WHEEL_POSITION;
- }
- }
- #ifndef RAM_FOR_FLASH
- free(measCnt);
- #endif
- return position;
- }
- #endif
-
- /***************************************************************************//**
- * @}
- ******************************************************************************/
-
- /***************************************************************************//**
- * @defgroup CTS_support
- * @ingroup CTS_API
- ******************************************************************************/
-
- /***************************************************************************//**
- * @ingroup CTS_support
- * @brief Determine which element within a sensor has the largest response
- *
- * This function compares and normalizes the change in capacitance to
- * determine which element has the dominant response. The deltaCnt
- * values for each element that exceed the threshold are also
- * converted from a 'raw' measurement to a percentage of the maximum
- * response.
- * @param groupOfElements Pointer to buttons to be scanned
- * @param deltaCnt Address to where the measurements are to be written
- * @return result index to the element which is dominant
- ******************************************************************************/
- uint8_t Dominant_Element(const struct Sensor* groupOfElements, uint16_t* deltaCnt)
- {
- uint8_t i;
- uint16_t percentDelta=0;
- uint8_t dominantElement=0;
- for(i=0;i<groupOfElements->numElements;i++)
- {
- if(deltaCnt[i]>=(groupOfElements->arrayPtr[i])->threshold)
- {
- if(deltaCnt[i] > ((groupOfElements->arrayPtr[i])->maxResponse))
- {
- deltaCnt[i] = (groupOfElements->arrayPtr[i])->maxResponse;
- // limit response to the maximum
- }
- // (maxResponse - threshold) cannot exceed 655
- // 100*(delta - threshold) / (maxResponse - threshold)
- deltaCnt[i] = (100*(deltaCnt[i]-(groupOfElements->arrayPtr[i])->threshold))/((groupOfElements->arrayPtr[i])->maxResponse - (groupOfElements->arrayPtr[i])->threshold);
- if(deltaCnt[i] > percentDelta)
- {
- //update percentDelta
- percentDelta = deltaCnt[i];
- dominantElement = i;
- }
- }
- else
- {
- deltaCnt[i] = 0;
- }
- } // end for loop
- return dominantElement;
- }
- #endif
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